Package javax.measure.spi

Interface SystemOfUnits

public interface SystemOfUnits

A system of units grouped together for historical or cultural reasons.
Common system of units are "SI" (System International), "Imperial" (British), "US" (US Customary). Nothing prevents a unit from belonging to several systems of units at the same time (for example an Imperial system would have many of the units held by the US Customary system).

Since:

1.0

Version:

1.1, June 21, 2018

Author:

Jean-Marie Dautelle, Werner Keil

See Also:

Wikipedia: International System of Units, Wikipedia: System of measurement

Method Summary

Modifier and Type	Method	Description
String	getName()
<Q extends Quantity<Q>> Unit<Q>	getUnit(Class<Q> quantityType)	Returns the default unit for the specified quantity or null if none is defined for the given quantity in this unit system.
Unit<?>	getUnit(String string)	Returns a unit with the given string representation or null if none is found in this unit system.
Set<? extends Unit<?>>	getUnits()	Returns a read only view over the units explicitly defined by this system.
Set<? extends Unit<?>>	getUnits(Dimension dimension)	Returns the units defined in this system having the specified dimension (convenience method).

Method Detail

getName

String getName()

Returns:

a name

getUnit

<Q extends Quantity<Q>> Unit<Q> getUnit(Class<Q> quantityType)

Returns the default unit for the specified quantity or null if none is defined for the given quantity in this unit system.

Type Parameters:

Q - the compile-time quantity type.

Parameters:

quantityType - the quantity type.

Returns:

the unit for the specified quantity.

getUnit

Unit<?> getUnit(String string)

Returns a unit with the given string representation or null if none is found in this unit system.

Parameters:

string - the string representation of a unit, not null.

Returns:

the unit with the given string representation.

Since:

2.0

getUnits

Set<? extends Unit<?>> getUnits()

Returns a read only view over the units explicitly defined by this system. This include the base and derived units which are assigned a special name and symbol. This set does not include new units created by arithmetic or other operations.

Returns:

the defined collection of units.

getUnits

Set<? extends Unit<?>> getUnits(Dimension dimension)

Returns the units defined in this system having the specified dimension (convenience method).

Parameters:

dimension - the dimension of the units to be returned.

Returns:

the collection of units of specified dimension.